Pneumonia

Question 1

Lobar

Answer 1

S. pneumonia, Klebsiella

Intra-alveolar exudate: consolidation, may involve entire lung

Question 2

Bronchopneumonia

Answer 2

S. pneumonia, S aureus, H influenza, Klebsiella

Acute inflammatory infiltrates from bronchioles into adjacent alveoli; patchy distribution involving >/= lobe

Question 3

Interstitial (atypical) pneumonia

Answer 3

Viruses (influenza, RSV, adeno), mycoplasma, legionella, chylamydia.

Diffuse patchy inflammation localized to interstitial area at alveolar walls; distribution involving >/= lobe

Generally more indolent.

Question 4

Lung abscess

Answer 4

S. aureus, anaerobes (bacteroides, fusobacterium peptostreptococcus)

Localized collection of pus in parenchyma.
Caused by bronchial obstruction; aspiration of oropharyngeal content (esp. in pts predisposed to loss of consciousness, alcoholic or epileptics)

Air fluid level on CXR.

Question 5

Hypersensitivity pneumonitis

Answer 5

Mixed type III/IV hypersensitivity reaction to environmental antigen
Dyspnea, cough, chest tightness, HA:
Often farmers and those exposed to bird